A vehicle such as an autonomous vehicle, a taxi or livery vehicle, etc., may be requested to pick up a passenger on demand. For example, a passenger using a communication device (e.g. smartphone) could request pickup at his/her current location by sending GPS (global positioning system) coordinates to the vehicle or a driver of the vehicle. The vehicle could then navigate to the GPS coordinates. A problem arises, however, in that, upon arrival at specified GPS coordinates, it may be difficult to identify a location of the target passenger with sufficient precision to actually pick the passenger up due to inaccuracies and/or imprecision provided GPS coordinates. Errors resulting from using GPS data can cause a vehicle to stop at a location separated from an actual location of a target passenger by as much as several meters, on a wrong side of a street or in a wrong driveway, etc.